[Closed] 27.5+???

[i]Are they just 27.5 rims with bad ass wide tyres? [/i]

basically but with frame/fork clearance to match. 2.8 - 3" seems to count as '+' without being 'fat'.

Fat bikes for those without conviction.

Yes but.

Expect 27.5+/B+ frames to have the new, wider axle standard and use different Q Factor cranks.

It's already here... But the industry seems to have taken fright at the fact that it's compatible with many 29er frames, so is now quickly retooling the idea to try and get people to buy new stuff.

Welcome to a year ago: [url= http://twentynineinches.com/2014/05/19/wtb-pushes-b-wheel-size-with-new-tirerim/ ]http://twentynineinches.com/2014/05/19/wtb-pushes-b-wheel-size-with-new-tirerim/[/url]

A year on and still so little available. I just wish they'd get on with it.

I like the look of the Genesis taken on it. Won't be available to buy till near end of the year though they say

Due April according to CRC (scraper etc) but velocity are already doing blunt35 in B+

Next up will be 26+ for long travel applications when all your 27.5 bikes have been consigned to marketers obsolescence.

Oh the ****ing great manatee.

Apparently it's gonna be the dogs goolies

Is this true?
I'm due to buy a new bike and was thinking about 27.5 but should I wait for this me walls ongoing all dancing wheel, mmm... Where have I heard all this befo

I wouldn't really bother, it's main application will be for shorter travel bikes and hardtails. If you're looking for a 150-170mm bike, 27.5 will probably stay the norm or move to 26+.

Unless that is.... you like long travel 29ers.... however despite Specialized's best attempts people haven't bought them up in any near as large quantities as 27.5 bikes.

These new 27.5+ bikes have the same contact patch area as a 29er (the 2.8 tread patterns are no wider in reality) they just blow up taller and fatter. Think of it as undamped suspension - a little bit pointless.

I still find it funny that People call 2.8 bouncy and Undamped but 2.5 is perfectly acceptable.

use different Q Factor cranks.

Boost uses same Q factor cranks. But 3mm further out chainline, to match the 6mm wider hubset.

[url= http://www.bikerumor.com/2015/03/17/wtb-launches-bridger-27-5-x-3-0-mtb-tires-new-sl8-saddle-carbon-rims/ ]WTB Bridger 27.5 x 3.0 [/url]

Boost uses same Q factor cranks. But 3mm further out chainline, to match the 6mm wider hubset.

so would that mean than on a geared on, with say a 10 speed cassette, the line would be quite acute in high gears ?

No - because the Boost 148 hubset is 6mm wider - 3mm each side - so the chainline is the same, relative to the sprockets.

What's happening with 29+?
I've been burying my head in the sand until we get a delivery date for the Rooster, so unaware of any developments, but is this wheel size now obsolete?

What's happening with 29+?
I've been burying my head in the sand until we get a delivery date for the Rooster, so unaware of any developments, but is this now obsolete?

Boost would work great for 29+ formats.

[quote=brant ]

use different Q Factor cranks.

Boost was really designed for 29ers but being applied to 27.5(+) as it can benefit that als, tho These 27.5+ forks and frames should fit 29er tyres too.

I'm being a bit thick here, [s]but surely with same q factor, and a wider hub, the chain at the axle, when in a low gear, is much further out from the centreline of the bike, therefore chainline between front rings and smallest sprocket is more acute than with a conventional hub ?[/s] 😳

just re-read brant's bit about the chainline at the front end being wider....

What’s happening with 29+? Not much, it seems, but it’s a lot of fun. I won a (admittedly, not that highly contested) cyclocross race on a Genesis Longitude with 29+ tyres. I think the riders there with cross bikes thought I was taking the piss. I wasn’t. Bump losses over less than putting-green-smooth grass were minimal with such big, supple tyres.

Can you make me a titanium one, Brant?

[quote=danj ]Can you make me a titanium one, Brant?I'm sure that's a big, (half) fat yes!

Or there's this
https://www.traversbikes.com/store/p8/Rudy_Fat_29__Frame.html

What’s happening with 29+? Not much, it seems, but it’s a lot of fun. I won a (admittedly, not that highly contested) cyclocross race on a Genesis Longitude with 29+ tyres. I think the riders there with cross bikes thought I was taking the piss. I wasn’t. Bump losses over less than putting-green-smooth grass were minimal with such big, supple tyres.

Can you make me a titanium one, Brant?

Ti 29+?

Sure.

I just got my B+(+) bike built up singlespeed. 3.25in Vee Rubbers.
We can do 29+ too. It's similar in the chainstay area, just a bit longer back end.

This is set up SS, but will do geared too. It's 148, using a spaced 142mm hub.

[img] [/img]

And there you have the real benefit of + sizes- they look awesome

In a 29er Turner Sultan :

[img] [/img]

In a 29er Turner Sultan :

That was the Turner Khan (Fatbike) not the 29er. I stood next to that this time last week 🙂 But it is awesome.

I still find it funny that People call 2.8 bouncy and Undamped but 2.5 is perfectly acceptable.

The point is, is that what is the point when the tread width is the same. Going up to 29 inch sized tyres introduces too many design compromises in long travel bikes.

Those 3 inch tyres just seem idiotic, how many people running 2.5 supertacky minions have ever thought....you know what...I need gripper, heavier slower tyres.

Let me guess, you'd recommend Procore instead 😆 😆 😆 😆 😆 😆

how do you get the chainline at the cranks 3mm further out without increasing q factor ?

The point is, is that what is the point when the tread width is the same. Going up to 29 inch sized tyres introduces too many design compromises in long travel bikes.

Those 3 inch tyres just seem idiotic,

Thanks for that, but I don't ride long travel bikes. Softer, 3 inch tyres have their pros and cons. It's not as simple as 'slower'; they roll better in certain situations, despite the additional weight.

Brant - I'll drop you a line. I've seen the Travers Rudy Fat and the Carver Gnarvester but neither is, off the peg, quite what I'm after.

Edit: I guess you might have been referring to the Turner... That's not my thing, but I'm happy that such bikes exist. Here's another bike that made me smile to see, but you will hate: http://www.lenzsport.com/detail.php?prodID=37

iainc - Member
how do you get the chainline at the cranks 3mm further out without increasing q factor ?
POSTED 22 MINUTES AGO # REPORT-POST

Offset the chainring.

Those 3 inch tyres just seem idiotic, how many people running 2.5 supertacky minions have ever thought....you know what...I need gripper, heavier slower tyres.

Having ridden 2.5" supertacky High rollers and 4" Floaters almost back to back, the floaters roll better, and grip better.

And I've said it before it's not 4" of undamped travel, well it is, but you're never likely to use it, it take the same force to compress a 4" tyre 2" as it does to compress a 2" tyre 2" at twice the pressure, which is about what people run them at (20someting PSI in a 2.2 vs 10Psi in a 4"). That 2nd 2" is just in reserve, sure you could compress it, but that would take double kind of force that gives a double snakebite. What you do get is a really supple tyre that deforms over smaller trail detrious, and as it's half the pressure (c.f. spring rate) of a conventional tyre it would only need half the damping anyway.

Just had to google what boost is.

Could they really not achieve that by telling the manufacturers to offset the existing rear hub by 3mm and even out the DS/NDS spoke tension in the process? The cranks fine, but everyone else could just have run the chainring in the outer rather than middle position.

And 110mm hubs? What does that help? 100mm<3", the tyres would (and did, see the insitigator) have fit.

The bike industry really does seem to be heading down Motorbike route of buying a complete bike, with only a few interchangeable bits.

And I've said it before it's not 4" of undamped travel, well it is, but you're never likely to use it, it take the same force to compress a 4" tyre 2" as it does to compress a 2" tyre 2" at twice the pressure, which is about what people run them at (20someting PSI in a 2.2 vs 10Psi in a 4"). That 2nd 2" is just in reserve, sure you could compress it, but that would take double kind of force that gives a double snakebite. What you do get is a really supple tyre that deforms over smaller trail detrious, and as it's half the pressure (c.f. spring rate) of a conventional tyre it would only need half the damping anyway.

I'll believe it when I've ridden one that grips better but has lower rolling resistance, over boggy ground maybe. Running 2.8 tyres on 50mm rims at low pressure already leads to too much squirm as it is. I think there are better ways of lowering tyre pressures without resorting to massive tyres, I think you can guess what this is.

Tom_W1987 - Member

I'll believe it when I've ridden one

You're keen to believe other things when you've not ridden them

At the end of the day Northwind - yes it's a hunch - however I don't see the point in someone holding off on a normal 27.5 bike. There have been loads sold now, if + sized tyres do take over then we will be seeing the return of 26 inch rims so that we can run massive tyres that fit 27.5 frames.

Could they really not achieve that by telling the manufacturers to offset the existing rear hub by 3mm and even out the DS/NDS spoke tension in the process? The cranks fine, but everyone else could just have run the chainring in the outer rather than middle position.

Yes

And 110mm hubs? What does that help? 100mm<3", the tyres would (and did, see the insitigator) have fit.

It adds 5mm per side clearance at the "slider bearing" area on the fork leg sliders. Gets a bit tight side-to-side otherwise.

That was the Turner Khan (Fatbike) not the 29er. I stood next to that this time last week But it is awesome.

Apparently that one is a Sultan - look about 1/4 of the way down this page :

http://www.pinkbike.com/news/275-tires-taipei-show-2015.html

"This Turner Sultan was retro-fitted with 27.5+ tires, and is the only complete bike we have found so far in Taipei with the mid-sized fat tires on it."

The XT crankset is saying Sultan to me. But I swear it had an 100mm BB shell and "fatbike wide" rear hub. I stood next to it in a meeting 🙂

Jetlag.

I'll believe it when I've ridden one

Now your opinion makes sense 🙂

It adds 5mm per side clearance at the "slider bearing" area on the fork leg sliders. Gets a bit tight side-to-side otherwise.

But seeing as most hubs are probably going to end up getting adapters to make them fit, why not just stick with 100mm at the dropout and build in 5mm shoulders at the dropouts?

Do you realise what this is doing to poor, innocent quokkas?
[img] [/img]

As if killing kittens wasn't bad enough!
[img] [/img]

Bring on quokka +

Now your opinion makes sense

As in your tyres, poor engrish on my part. I've ridden a few fat bikes and found them to be cumbersome and slow.

Do you realise what this is doing to poor, innocent quokkas?

😆

http://www.bikerumor.com/2015/04/10/tpe15-vee-tire-co-grows-apache-road-tire-to-28mm-blows-up-w-monstrous-5-05-fat-biker/#more-99055

More info on the Turner (suggests it's not a stock model as I suspected)